Underwater searchers, airborne units and mountain rescue teams yesterday joined the hunt for Claire Hart which began on Thursday after she disappeared near her home in the village of Eaton, Cheshire.
The teenager's coat has been found near to the field where she was seen talking to a youth dressed in combat gear with a shotgun slung over his shoulder soon after she left her home on the two-mile walk to Dane Valley school.
On Saturday evening magistrates granted police a 36-hour extension to allow continued questioning of a local man in custody.
Volunteers from the Peak District mountain rescue team looked for the missing girl over the weekend, and more than 50 police officers worked alongside airborne units and underwater search teams who have been searching the River Dane.
Some homes in Eaton have already been searched, police said.
Superintendent Derek Barnett, in charge of the investigation, said both parents were "distraught". "As the search enters a fourth day our concerns grow and we must accept that the situation is not looking good," he said. "But, nevertheless, our officers are fully committed and are doing everything they can to find Claire."
Sergeant Chris Jones of the Cheshire Police operational support unit is leading the search from a base set up in the grounds of Claire's school.
"The sort of area we are looking in is from open fields to an awful lot of difficult terrain," he said. "There is an industrial area right in the middle of the area, also disused drainage and ditches.
"In the woods there are tough under bushes which can be almost impenetrable, plus caves and cuttings."
Claire, who is said to look young for her age, wears glasses and has collar-length brown hair, had just returned from a school holiday in France. She was last seen wearing her school uniform of grey skirt, white shirt, black tie and blue sweatshirt. No clothes were missing from her home, police said.
Residents in Eaton described Claire Hart as a happy, lively girl who could be a little naive and trusting.Reuse content